Magnetic oil cleaner for screw machine



Aug. 21, 1956 P. w. NIPPERT MAGNETIC OIL CLEANER FOR SCREW MACHINE Filed Dec. 31. 1952 VENTORL MMM United States Patent MAGNETIC OIL CLEANERFOR SCREW MACHINE PaulW. Nippert, Columbus, Ohio, assignor to The Nippert Electric Products Company, Columbus, Ohio, a corporation of Ohio Application December 31, 1952, Serial No. 328,880

6 Claims. (Cl. 210-1.5)'

My invention relates to metal Working machines and more particularly to apparatus for removing metal particles from coolant oil or the like.

It has heretofore been common practice to provide metal working machines, such as screw machines and the like, with conveyor means for carrying away metal particles and cuttings which have been removed from work stock in the forming of metal parts. Such conveyors are commonly in the form of an endless belt which passes beneath the cutting head of the machine with such belt also passing through a sump or tank in which the coolant oil is contained. The sump serves as a reservoir from which coolant oil is pumped to the cutting head of the machine. After the oil contacts the cutters and work stock it is returned to the sump and again recirculated past the cutters. In the course of operation of the machine the coolant oil picks up small particles of metal and circulates such particles through the fluid circuit. As is well known in the art, the presence of such metal particles in the coolant oil is undesirable since they mar the surfaces of the articles being machined, thereby destroying the finish thereon. In addition, such metal particles are detrimental to the oil circulating pump and the edges on the cutters causing the life of the pump and cutters to be materially shortened. In instances heretofore, the fluidcircuit of the coolant oil has, on occasion, been run through filters to remove the metal particles. Such filters have received limited acceptance in the art due to their expense and due to clogging of the filter screens by the metal particles. My invention provides an inexpensive and highly effective means for removing the objectionable metal particles from the coolant oil carried in the sump.

In metal working machines having a chip conveyor belt which passes through the sump, I provide magnetic means on the conveyor belt. Such means may be formed as flights secured to the outer surface of the conveyor belt and extending laterally to the path of the belt. When the conveyor is in operation the magnetic means is passed through the sump, and hence the coolant oil, with the result that the metal particles are magnetically attracted and collected by the magnetic means. In addition, 1 provide means for removing the metal particles from their magnetic association with the collecting means. For this purpose a flexible blade may be positioned in the path of the conveyor belt so as to be engageable with the magnetic means as it is carried past the blade by the moving conveyor.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of embodiment of the invention is clearly shown.

In the drawings:

Fig. 1 is a front elevational view, partially in section, of a metal working machine to which the present invention is adapted, with the section being taken along a vertical plane through the sump of the machine;

Fig. 2 is a perspective view of. a magnetic: flight utilized in the present invention;

Fig. 3 is an end sectional view of the magnetic flight of Fig. 2 with the section being, taken along the line 3-3 of'Fig. 2;

Fig. 4 is side elevational. view of the magnetic flight of Fig. 2 and showing such flight mounted on a conveyor;

Fig. 5 is an end elevational view, partially in section, of the magnetic flight of Fig. 2 and associated means for removing metal particles from said flights; and

Fig. 6 is a partial perspective view, partially in section, of the metal particle removing means of Fig. 5-.

Referring to the drawing, and more particularly to Fig. 1, a frame for a metal. working machine is indicated generally at 10. A metalworking head 11 is mounted to the frame. Such head is provided with cutters 12 or other suitable means for working metal. Onthe lower portion ofthe frame 10, a sump 14 is provided to serve as a reservoir for coolant oil carried. therein and indicated at 15.

Below the cutting head 11,. anendless conveyor 17 is positioned to catch metal particles discharged from the cutting head 11 when work stock is being operated upon by the metal working machine. The conveyor 17 is operated in a counterclockwise direction as seen in Fig. 1, so that the metal particles 19- are conveyed to the left and into a receptacle 21.

A plurality of flights 23 are. located atintervals along the conveyor 17 for engaging the metal particles. and moving them to the receptacle 21 I choose to form at least one or a plurality of the flights as magnetic bars extending in a direction transverse to the path of the conveyor and mounted thereon. Such a. magnetic flight is shown in detail in Figs. 2,. 3 and 4 and will be described later herein.

As is seen in Fig. l, the path of theconveyor 17 extends through the coolant oil carriedinsump 14. Certain of the metal particles 19 become dispersed in such coolant oil during the operation of the machine since the coolant oil is continually pumped in a fluid circuit, not shown, past the cutter 12. It is desirable to remove these metal particles from the coolant oil so that a better finish can be obtained on the work piece being operated upon by the head 11. Hence as the conveyor 17- passes through the coolant oil 15 any of the flights 23,. which are formed as magnetic members, will attract and collect metal particles in the coolant oil as such magnetic flights are carried therethrough, by the moving. conveyor. Such a magnetic flight is indicated at 23a in Fig. 1.

Adjacent to the receptacle 21,. means for removing metal particles collected. by the flight 23a is provided in the path of. the conveyor 17 so as to engage the magnetic flight 23a as it passes thereby. Such means ispreferably formed as aflexible blade 25 which ismountedto the frame 10 by suitable brackets 26. Hence: it will be seen that as the conveyor 17 rotates in a counterclockwise direction the magnetic fiightZSzz, upon which metal particles have been collected, is carried past the flexible blade 25 and engaged thereby so that the metal particles are removed from the magnetic flight 23a and caused to fall into the receptacle 21.

Referring to Figs. 2, 3 and 4, a magnetic flight 23a of Fig. 1 is shown in detail. A magnetic member 30, preferably of horseshoe-shaped cross-section, is shown mounted in a non-magnetic casing 32. A non-magnetic bar 33 is longitudinally disposed in the trough of the magnetic member 30. With this construction only the surfaces 35 and 36 of the magnetic member 30 will be exposed to magnetically attract metal particles. In this manner the metal particles will be collected by only surfaces 35 and 36 which are adapted to be scraped clean 3 of the particles by the blade 25 later to be described in detail.

To mount the flight 23a to the conveyor, a bracket 38 is bolted to the assembly of magnetic and non-magnetic elements'by means of the bolts 40. and nuts 41. The.

bolts 40 may be extended through non-magnetic bar 33, the magnetic member 30 and the casing 32 in the manner shown so that these components are secured together as well as being secured to the bracket 38.

The bracket 38 extends beyond each end of the flight 23a to form flanges 44. Fasteners 45, in the form of bolts or rivets, are used to secure the flanges 44 to the conveyor 17 as is best seen in Fig. 4.

Referring to-Figs. and 6, the apparatus for removing the magnetically'attracted particles from the magnetic flights 23a is shown in detail. Such apparatus comprises the flexible blade 25, formed of ruber or the like, which blade is clampingly retained between two blade mounts 50 and 51. The blade mount 50 is secured to the frame by means of brackets 26 each of which contains a slot 53. A bolt 54 is passed through each slot 53 to adjustably mount the blade and bracket assembly to the frame. The blade mount 51 is removably secured to the blade mount 50 by means of the bolts 56 and the nuts 57 so that the flexible blade can be replaced when worn.

In Fig. 5 the normal position of the blade 25, relative to a moving magnetic flight 23a, is shown by solid lines. It will be noted that the forward side 60 of the magnetic flight 23a is engaged by a face 61 of the flexible blade 25 as the flight approaches the blade. The blade is thereby caused to yield to the angular configuration shown by the dotted lines in Fig. 5. The magnetic surfaces 35 and 36 are then drawn past the edge of the flexible blade 25 as movement of the conveyor 17 carries the magnetic flight 23m from the position shown by the solid lines to the position shown by the dotted lines in Fig. 5. The metal particles are thereby removed from magnetic engagement with the surfaces 35 and 36.

It will be noted that the removable blade mount 51 is provided with a beveled surface 63 to eliminate one of the square corners therefrom. This allows the metal particles to slide freely away from the removable blade mount 50 and downwardly into the receptacle 21 to form a pile of particles at 65 in Fig. l.

The bulk of the metal particles discharged from the cutting head 11 fall directly onto the conveyor 17. The non-magnetic flights 23 serve to help move such particles along the conveyor to the left end thereof, as viewed in Fig. 1, at which end the particles are caused to fall downwardly into the receptacle 21 to form a pile of particles at 66 in Fig. 1. Hence it will be seen that the particles removed from the coolant oil by the magnetic flights 23a are deposited at 65, whereas the metal particles falling directly onto the conveyor are deposited below the left end of the conveyor at 66.

While the form of embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow:

I claim:

1. In a metal working machine, in combination, a head portion from which large and small metal particles are discharged, a sump adapted to carry coolant oil or the like, a conveyor having a path of travel extending beneath the head in the path of particle discharge and through the sump, and flights on the conveyor extending transversely to the path thereof and adapted to engage and move metal particles discharged from the head directly onto the conveyor, with at least one of said flights being magnetic for collecting small metal particles suspended in the coolant simultaneously with movement of said metal particles discharged directly onto said conveyor, and means for removing said particles from magnetic retention at a predetermined point along said conveyor path.

2. In a metal working machine, in combination, a head portion from which metal particles are discharged, a sump adapted to carry coolant oil or the like, a conveyor extending beneath the head in the path of-particle discharge and through the sump, flights on the conveyor with said flights forming surfaces extending upwardly from said conveyor for engaging particles discharged on the conveyor surface, with at least one of said flights having a magnetic surface for collecting metal particles suspended in the coolant, and means disposed in the path of the conveyor and engageable with said magnetic surface for removing metal particles therefrom.

3. In a metal working machine, in combination, a head portion from which large and small metal particles are discharged; a sump adapted to carry coolant oil or the like; a conveyor forming a moving surface extending beneath said head in the path of particle discharge and extending through said coolant; a flight mounted on said conveyor and forming a non-magnetic surface extending outwardly from said conveyor surface and transverse to the path of travel of said conveyor for moving particles discharged on said conveyor surface, said flight having a magnetic surface for collecting the small metal particles in the coolant simultaneously with said movement of the particles discharged directly on the conveyor surface, and means for removing particles from said magnetic surface at a predetermined point along said conveyor path.

4. The apparatus defined in claim 3 wherein said means comprises an element disposed in the path of said conveyor and engageable with said magnetic surface for removing metal particles therefrom.

5. The apparatus defined in claim 3 wherein said means comprises a resilient blade mounted at a point along the path of the conveyor and engageable with said magnetic surface for removing metal particles therefrom.

6. The apparatus defined in claim 3 wherein said means comprises an element disposed in the path of said conveyor and engegeable with said magnetic surface, and wherein said means includes an adjustable mounting for said element relative to said conveyor.

References Cited in the file of this patent UNITED STATES PATENTS 

